JP3161014B2 - Gear drive mechanism - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a gear drive mechanism in which a plurality of gear trains have a toothless gear, which requires regulation of the meshing position of the toothless gear.

[0002]

2. Description of the Related Art In recent years, as a means for sequentially realizing two or more types of different operations, a gear drive mechanism having a toothless gear in a plurality of gear trains has been adopted.

Hereinafter, an example of a gear drive mechanism having the above-described conventional toothless gear will be described with reference to the drawings.

FIG. 3 is a partially cutaway perspective view showing a gear drive mechanism in which a conventional plurality of gear trains include a toothless gear and the meshing position of the toothless gear needs to be regulated. In FIG. 3, reference numeral 31 denotes a gear in which three gears 31a, 31b, and 31c are stacked coaxially and rotate integrally. The driving force of a driving source such as a motor is transmitted to the gear 31a, and arrows G and H
It is rotatable in both directions. Also, the gear 31b and the gear 3
Reference numeral 1c denotes a toothless gear having a toothless portion having no tooth profile other than a limited range. The tooth portion of the toothless gear 31b is attached so as to mesh with the gear 33b, the tooth portion of the toothless gear 31c is installed so as to mesh with the gear 32a, and the gear 32a always meshes with the gear 33a, and the gear 33a Is always engaged with the rack 34. The gears 32a and 32b are coaxially stacked gears that rotate integrally.

[0005] The operation of the gear drive mechanism having the toothless gear configured as described above will be described below.

In the configuration of the gear train shown in FIG. 3, the transmission path of the driving force is such that when a driving force rotating in the direction of arrow H is applied to the gear 31a, in the state of FIG.
are engaged with each other, the rotation of the toothless gear 31c is transmitted to the gear 32a, and the rotation is further transmitted to the gear 33a, so that the rack 3
4 is driven in the direction of arrow F. At this time, the toothless gear 3
1b, the missing tooth portion faces the gear 33b, and the missing gear 3
The rotation of 1b is not transmitted to the gear 33b. When the gear 31 further rotates in the direction of the arrow H, the tooth of the toothless gear 31c is disengaged from the gear 32a, and the gear 31 rotates but the rack 34 is stopped. When the gear 31 further rotates in the direction of arrow H, the tooth portion of the toothless gear 31b and the gear 33b mesh with each other to drive the rack 34 in the direction of arrow E via the gear 33a. In this manner, the rotational motion of the gear 31 can be changed to the reciprocating motion of the rack 34.

[0007]

However, when a plurality of missing gears are included in the conventional plurality of gear trains as described above, the gear 32a and the gear 33
b is in a state of not engaging with all the gears of the gear 31. In this state, when the gear 32a or the gear 33b is next engaged with the tooth portion of the toothless gear, the gear 32a and the toothless gear 3
Even if the meshing with the toothed portion 1c is good, the meshing between the gear 33b and the toothed portion of the toothless gear 31b becomes defective. That is, the timing of the engagement is important. If the timing is deviated, functional failure due to poor meshing of the toothless gear and a collision noise at the time of meshing are generated, resulting in deterioration of product quality. In order to solve such a problem, complicated gear matching at the time of assembling the gear train is required. Conventionally, as a means for facilitating the complicated tooth matching, marking was made at the time of assembling by marking the tooth profile to be engaged.However, there is a possibility that assembly failure may still occur with the visual dependent method. There is a problem that man-hours for work and the like are required.

SUMMARY OF THE INVENTION In view of the above-mentioned conventional problems, the present invention is directed to a gear drive mechanism in which a plurality of gear trains include a toothless gear, and which requires regulation of the meshing position of the toothless gear. An object of the present invention is to provide a means for easily realizing meshing position regulation, eliminating poor meshing of a toothless gear, and reducing collision noise at the time of meshing.

[0009]

Means for Solving the Problems] gear drive of the present invention in order to solve the above problems, placed in a plurality of gear trains
Gear driven by a drive source , and this missing gear
A first gear that meshes with and transmits a driving force;
A second gear coaxially rotating with the car, and this second gear
With a gear or rack of the driven-side last stage
The number of teeth of the second gear is a multiple of the number of teeth of the first gear.
And the driving force of the driving source is transmitted to the first gear by the first gear.
Depending on the engagement with the gear,
A configuration with a gear drive mechanism to transmit to the click, before
The second gear has a plurality of meshes corresponding to the number of teeth of the first gear.
A first protrusion for position control, and the first protrusion is provided.
Is provided at a position corresponding to the
Regulates the meshing position of the gear or rack with the first gear
The second protruding portion is connected to the gear or rack at the last stage on the driven side.
And the fitting between the first projection and the second projection.
Regulating the engagement position of the first gear with respect to the <br/> partial gear in a state of partial gear by engagement does not mesh with the first gear
It is configured as follows.

[0010]

According to the present invention, the first protrusion is provided by the above structure.
The toothless gear meshes with the first gear by the engagement between the first gear and the second protrusion.
Meshing of the first gear with the missing gear in a non-meshing state
Because it is configured to regulate the meshing position, it realizes the position regulated state with the gear train combined, eliminating the need for complicated tooth matching, and simply combining the gear train to reduce the missing tooth gear The poor engagement is eliminated.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a gear driving mechanism having a toothless gear according to the present invention will be described below in detail with reference to FIGS.

FIG. 1 shows a gear drive mechanism according to an embodiment of the present invention in which a plurality of gear trains include a missing gear and the meshing position of the missing gear must be regulated. FIG.
FIG. 4 is a perspective view showing a meshing position regulating projection .

In FIG. 1, reference numeral 1 denotes three gears 1a, 1
b and 1c are coaxially stacked gears that rotate integrally,
The driving force of a driving source such as a motor is transmitted to the gear 1a, and the gear 1a is rotatable in both directions of arrows G and H. Also, the gear 1b
The gear 1c is a toothless gear having a toothless portion having no tooth profile other than a limited range. The tooth portion of the toothless gear 1b is the gear 3b
The toothed portion of the toothless gear 1c is mounted so as to mesh with the gear 2a.
The gear 2a is always meshed with the gear 3a, and the gear 3a is always meshed with the rack 4. The gears 3a and 3b are coaxially stacked and integrally rotated. Also, 4a
Is a position regulating projection provided on the rack 4 at the last stage on the driven side.
The portion 3c is a position regulating protrusion provided on the gear 3a meshing with the rack 4 and having a shape tapered toward the tip, and is fitted with the position regulating protrusion 4a provided on the rack 4 to regulate the position. I do. The gear 3b integrated with the gear 3a is designed to mesh with the missing gear 1b having missing teeth. The number of teeth Z3a of the gear 3a is the number of teeth Z3b of the gear 3b.
(N is an integer).

The operation of the gear driving mechanism having the missing teeth configured as described above will be described below.

In the configuration of the gear train of FIG. 1, the transmission path of the driving force is such that when a driving force rotating in the direction of arrow H is applied to the gear 1a, in the state of FIG.
And the rotation of the toothless gear 1c is transmitted to the gear 2a, and the rotation is further transmitted to the gear 3a to drive the rack 4 in the direction of arrow F. At this time, the toothless portion of the toothless gear 1b faces the gear 3b, and the rotation of the toothless gear 1b is not transmitted to the gear 3b. Gear 1
Rotates in the direction of arrow H, the tooth portion of the toothless gear 1c is disengaged from the gear 2a, and the gear 1 rotates but the rack 4 rotates.
Is stopped. When the gear 1 further rotates in the direction of arrow H, the tooth portion of the toothless gear 1b and the gear 3b mesh with each other to drive the rack 4 in the direction of arrow E via the gear 3a.

In order to simplify the description of the position regulating projections 3c and 4a , the number of teeth of the gear 3a is twice the number of teeth of the gear 3b, and the number of teeth of the gear 3a, the gear 2a and the toothless gear 1c is increased. Reduction ratio, gear 3a, gear 3b and missing gear 1b
The case where the reduction ratios in the combination of the two are equal will be described below.

In this case, when the gear 3b rotates by one tooth, the gear 3a rotates by two teeth. Conversely, if the gear 3a rotates by one tooth, the gear 3b rotates by half a tooth. Considering the normal meshing between the gear 3b and the toothless gear 1b, poor meshing with the toothless gear occurs when the gear 3b rotates half a tooth from the normal meshing position. That is, in order to regulate the position of the gear 3b and the toothless gear 1b in a normal meshing state, the meshing position of the gear 3a and the rack 4 at the last stage on the driven side with respect to the normal meshing tooth of the toothless gear 1b and the gear 3b. Needs to be regulated for every second tooth of the gear 3a. Gear 3
b and the toothless gear 1b with the gear 3a for a normal meshing tooth
Position regulating protrusions on both sides of the bottom of the tooth and the tip of the rack 4
By providing the parts 3c and 4a and fitting them together, it is possible to easily realize that poor meshing of missing teeth does not occur.

Similarly, when the number of teeth of the gear 3a is three times the number of teeth of the gear 3b, it is necessary to regulate the position for each third tooth of the gear 3a. In this case, the gear 3b and the toothless gear 1b are provided with position regulating projections 3c and 4a on two adjacent teeth on the bottom of the gear 3a and the tip of the rack 4 with respect to the normal meshing teeth.
Is provided, it is possible to easily realize that poor engagement of the toothless gear does not occur.

As described above, according to the present embodiment, there is a missing gear in a plurality of gear trains, and in a gear driving mechanism which requires regulation of the meshing position of the missing gear, the lack of meshing of the missing gear can be reduced. Can be easily solved.

[0020]

As described above, the present invention provides a plurality of gear trains.
Toothless gear driven by a drive source in the
A first gear meshing with the toothless gear and transmitting a driving force;
A second gear coaxially rotating with the first gear,
The last stage gear or rack meshing with the second gear
Wherein the number of teeth of the second gear is a plurality of times the number of teeth of the first gear
And the driving force of the driving source is
The last stage gear on the driven side due to meshing between the gear and the first gear
Or with a gear drive mechanism configured to transmit to the rack
The second gear has a plurality of gears corresponding to the number of teeth of the first gear.
The first projections for regulating the number of engagement positions are provided.
The driven member is provided at a position corresponding to the protrusion
Meshing position of the last gear on the side or the first gear of the rack
The second projection that regulates the position is connected to the gear at the last stage on the driven side.
Or the rack is provided with the first protrusion and the second protrusion.
Missing tooth gear does not mesh with first gear due to fitting with the raised part
In this state, the meshing position of the first gear with respect to the toothless gear is
It is those configured to restrict, eliminates the need for multiple <br/> sloppy meshing during gear train assembly, is to simply eliminate the engagement failure of the partial gear by combining a gear train
I can . Further, the number of man-hours can be reduced by simplifying the combination work, and the realization of assembly by an automatic machine can be facilitated.

[Brief description of the drawings]

FIG. 1 is a perspective view of a gear driving mechanism according to an embodiment of the present invention.
Figure

FIG. 2 is a perspective view showing the engagement position regulating protrusion.

FIG. 3 is a perspective view of a conventional gear drive mechanism .

[Explanation of symbols]

Reference Signs List 1 Gear having missing tooth gear 1b, 1c Missing gear 2a Gear 3a Gear (second gear) 3b Gear (first gear) 3c Projection (first projection) 4 Rack 4a Projection (second projection) )

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-49-36931 (JP, A) JP-A 63-25855 (JP, U) (58) Fields investigated (Int. Cl. ⁷ , DB name) F16H 27/00-27/10

Claims (1)

(57) [Claims] 1. A to Oite drive source in the plurality of gear trains
A toothless gear driven Ri, driving in mesh with the partial gear
A first gear to which power is transmitted;
A second gear that rotates on the body and a driven gear that meshes with the second gear
And a gear or rack at the side of the second gear.
The number of teeth is a reduction ratio that is a multiple of the number of teeth of the first gear.
And the driving force of the driving source is meshed between the toothless gear and the first gear.
Transmission to the last gear or rack on the driven side
Configuration was a gear drive mechanism as the the second gear meshing a plurality corresponding to the number of teeth of the first gear
A first protrusion for regulating the fitting position is provided, and the first protrusion is provided.
The driven-side final stage provided at a position where
The position of the gear or rack meshing with the first gear
The second protruding portion is driven by the gear or
Are provided on click, against the said partial gear in a state where the first protrusion and the partial gear by engagement between the second projection portion is not engaged with the first gear
A gear driving mechanism configured to regulate a meshing position of the first gear .